ZEN NDI GradBG - Colour Gradient Background generator

The basic functionality is in generating a 4-way gradient-filled image using
selectable colours for the four corners of the rectangle, although pairs can be
set to the same value in order to achieve a simple 2-way gradient. The gradient
image can either remain static or the colours can rotate in a clockwise (CW) or
anticlockwise (CCW) direction. A slider control adjusts the period between
colour changes (i.e. faster rotational speed as the slider moves to the right).

The
gradient image can either fill the screen, be horizontally (H-Split) or
vertically mirrored (V-Split) as two half-size rectangles, or be mirrored both
horizontally and vertically (in Quad mode) using quarter-size rectangles. The
Cloud overlay option adds a fixed fractal noise pattern, self-keyed over the
background.

There are five Presets which hold different configurations (colours, patterns,
etc). The Paste button will copy the last used preset to the current one (e.g.
to copy number 3 to number 5, select 3 then select 5 and click on Paste)

On exit, a "last.gbg" file will be created with the current group of five
presets, plus it's possible to save a "default.gbg" file from the main
right-click drop-down
menu in the title bar. If the default file exists, it will be loaded on start-up.
Click the "Load last" button to load the last used preset group. Multiple
instances of the app can be run on the same PC, with the NDI ident names being
sequentially auto-numbered. The "watermark" logo will disappear after several
minutes of use.

ZEN NDI RTx (NDI Receiver-Transmitter)

One of the "features" of NewTek's NDI is that connections between devices are all
point-to-point, such that if two receiving devices are connected to a single
source sending video, then two streams are required - meaning twice the
bandwidth of a single stream. The more connections you add, the more bandwidth
is required. Given that NDI is intended
for production environments rather than mass-audience video streaming, this is
not usually a problem, but it may be desirable for a number of remote stations
to be able to monitor a single source - the main output from a switcher, for
example. In these circumstances there could be a high bandwidth requirement over
the network connection from that source, potentially more than a single node can
handle. One solution is to retransmit the NDI stream from another PC on the
network via the equivalent of a "Relay" or "Repeater" transmitter (as used in TV/Radio
transmission). A kind of NDI "Distribution Amp" if you like.

My NDI-RTx was created because I wanted something to run on a remote PC to
perform an "NDI loopback" so I could monitor the effects of a round-trip over a
network, measured on the same PC as the NDI source.

After I started using it I then realised that something like this can be used
as a sort of "NDI CDN" to distribute network bandwidth by creating remote
"splitter-nodes" at various locations and offload work from the switcher PC.
Bear in mind that this utility was created for in-house testing so may not be
the most robust code, and given that it was intended for simple loopback
applications it has not been tested with large numbers of clients, but if anyone
out there would like to do some tests with it you can download a test version
below. Unzip into it's own folder
and install the VisualC libraries (DLLs) if needed and it should be good to go.

The current edition, v1.0.3.0, now includes a freeze-frame function, local audio
monitoring and a video confidence monitor, has been recompiled with the NDI v2.0
code, and looks like this:-

Hopefully, usage is fairly straightforward and there's a ReadMe file in the download with further notes.

After you open the app it should start to detect active NDI source names. Sources will subsequently be added/removed automatically or you
can press the Disconnect button to re-trigger checking.
Note that "Exclude local sources" is ticked by default.

Click on a Source in the list to make a connection. You will see some stats
about the connected source along the top of the window:- IP address/port, Source
name, video resolution/frame-rate, audio channels/sample-rate and timcode (if
present). The right-hand indicator light will be purple for a video+audio
source, red for video-only, blue for audio-only.

To select a different source it is necessary to first Disconnect the existing
source. The connection indicator light should go out and the top part of the display will look
a bit like this when no source is connected:-

Note that multiple copies of NDI-RTx can be run on the same PC, each of which
will be allocated a different NDI Source name. (eg the first copy will have an
NDI name ending RTx 1, then RTx 2, etc)

The more recent versions also include an audio meter/monitor function (for
Ch1+2), as above. Click on the
upper/middle/lower part of the speaker icon to get full-level/dimmed/muted audio
output.

This software is supplied
"as-is", with no warranty or guarantees of being fit for any particular purpose!

Martin Kay - May 2016 - Apr 2017

The NDI "No Audio" Meter

A simple Red-Amber-Green audio display designed to a provide an alert when the
audio level of the selected NDI audio stream falls below a certain level. Detection thresholds can
be adjusted and the No Audio state both flashes red and generates audio beeps.
Also detects of breaks in the stream from the selected NDI source.

For a limited period, the old version (1.0.0.8) of NDINoAudioMeter is available
for
download from here. See the included ReadMe
file for further info. The link for the current version is below.

Revised version 1.1.0.0 now includes a video preview window and has been
recompiled using the NDI2.0 code. Functionality is otherwise the same as the
previous version, albeit with a rearranged layout to the controls.

An alternative to NewTek's NDI Connect (Pro), explicitly designed to expose the
hardware video processing features of Magewell's Pro Capture family of PCIe
cards. Use a Pro Capture Quad card to create four NDI sources, for example.

NDIZender is based on the NDI Sender example application that was introduced
into the Magewell Pro Capture SDK for Windows at the start of September 2016.
Prior to that I'd been developing the quad-input "NDI sender" (above), but in
many ways the SDK example looked more complete - it had audio input & monitoring
for example - so I thought I'd take a bit of time out and see if I could tidy it
up and add a few important features, like support for PAL frame-rates, all of
which looked simple enough.

Over two months later, after much "tidying up", some debugging of underlying
functionality, and the addition of many new controls and features, NDIZender
bears only a passing resemblance to the original in the Magewell SDK.

The beta version from Dec-2016 can be downloaded below,
along with other NDI apps.

An NDI Routing Switcher

During the Christmas break I was experimenting with the Routing functions
introduced in v2.0 of the NDI SDK. These functions allow the creation of
software routers for NDI signals which can effectively switch between NDI
sources with no added latency and virtually zero CPU usage. As a
proof-of-concept sample application I created a 6in-2out switcher - which seems
to work as expected and, for some applications, if only as an auxiliary switcher,
could be a really useful tool for some people. Note that the switching can be
done from anywhere on the network, and that the actual NDI streams do not have
to pass through the computer running the Router software, which effectively just
acts a "front panel remote" to the virtual NDI router.

In the illustration below, the router/switcher is configured like a 6-input
cuts-only A-B switcher, with Preview (B) & Program (A) buses/outputs and a Cut
button which swaps the contents of the busses.

What we're about . . .
ZEN is not a traditional Audio-Visual dealer who started selling computers,
nor is it a computer shop that also sells video products. You won't
get any salesmen giving you the "hard-sell" when you call, just
straightforward advice and information - which for some callers is the
knowledge that they don't need to buy whatever it is they thought they
needed! Above all you'll be dealing with someone with a wide range of
experience and knowledge of both PCs and video production. We're not the
biggest, nor necessarily the cheapest, but we are one of the longest
established computer/video specialists in the UK.

Company history . . .
ZEN was started in the 1980s by Martin Kay, then working for ITV at
Granada's Manchester studios, who built his first 6502-based computer in
1979 from an Ohio Scientific kit, bought in the USA whilst working as a
Sound Recordist on a
film shoot for World In Action. With the advent of the Amiga, which could be gen-locked
to a video source, Martin started writing a variety of video-related software. This
included subtitling & tele-prompting, ident clocks, scoring software for
sports & gameshows, and specialist software to mimic other computer
displays for
use in TV film dramas like Cracker, Prime Suspect and A Touch of Frost.
Martin left Granada in 1993 to concentrate on his computer-video activities
with ZEN, following a natural path into non-linear editing systems,
for many years the main business activity, although he still maintains an active
interest in video production.